Being economical with the truth is part of our development – and is essential to get through a day in the office, writes LUCY KELLAWAY

AT THE Chelsea Flower Show last Monday I saw a former British prime minister talking to a former newspaper editor.

The ex-PM was smiling broadly and expressing delight at the chance meeting.

Yet about five minutes earlier he had been overheard saying something disparaging about the ex-editor and tried to duck behind an oversized flower pot to avoid having a conversation.

What does this say about the politician? That he is a duplicitous weasel? Or that he has the polite charm that we require of the most successful people?

Last week, I heard Dorothy Rowe, the Australian psychologist, talking on the radio about her new book, Why We Lie. Even very small white lies, she argued, are motivated by a fear of damaging our idea of ourselves as people and will catch us in the end.

This is far too deep for me. Lying is surely caused as much by pragmatism as fear. In my experience, it can be jolly useful. And tests have shown that it doesn’t always catch up with you at all.

In the latest issue of the Harvard Business Review is an article stating that powerful people are better liars.

Researchers from Columbia Business School asked bosses and staff to steal a $100 note and then convince someone that they hadn’t taken it – a trick that bosses could pull off far more successfully than their employees.

Earlier this month, another study was published by psychologists at the University of Toronto showing that children who start lying by the age of two are more likely to be successful when they grow up.

Lying is an important developmental stage: it means you can hold the truth at the back of your mind while saying something else at the same time.

Together, these two surveys seem to paint a scary picture. The cleverest are propelled to the top on a wave of lies, and once in power, are compelled to lie even more.

Before you know it the whole world is being run by Kenneth Lays and the worst sort of lying banker. I don’t think it proves this at all.

There is extreme lying, which is always bad. But there is also modest lying that is not bad; indeed it is absolutely essential to get through a day in the office.

What is needed is more than being economical with the truth, it’s being sophisticated with it.

People who thrive, like the ex-PM, have reached the further developmental stage of knowing just how far they can tell different stories to different people while still (one hopes) holding on to some core of honesty.

It is knowing which lies harm and which help; understanding that truth is a bendy concept, and bending it to the best shape at the time.

Only the very stupid, the very rude and the very young never lie in this way.

In the British sitcom Outnumbered, the young daughter Karen is funny because she never lies.

When she opens the door to a woman trying to sell something and is asked where her father is, she gazes at the woman angelically and says: “He’s on the toilet.”

Sometimes you come across grown-ups who have progressed no further than this child.

Last week, I bumped into someone who I had invited to my book launch party but who hadn’t come.

Sorry not to have seen you, I said. “I get asked to a lot of parties. I thought I could give a miss to yours,” she explained.

Such compulsive truth-tellers don’t last in organisations for more than five minutes. Offices are glued together with lies.

We pretend to like people we work with. We must pretend to be satisfied with our jobs. We must pretend to think our company is better than the competition. By accepting a place in any hierarchy, you are bending yourself out of shape.

So when asked by an anxious editor “how are you getting along with your column?” I say: “Nearly done. It’ll be with you by six.”

The first bit is a lie. The truth is that I have wasted time and the column is barely begun. The next bit is true. Deadlines must be met. I am proud of my lies. Proud of my ability to adjust behaviour according to the circumstances, and hope I have passed on the gift to my children.

Last week I asked my 17-year-old daughter how many lies she’d told that day. None, she said. Was the answer in itself a lie, I worried.

Or, even worse, was she not advanced enough to have learnt how to lie? But then I reflected that it was only 8am, she had just stumbled out of bed and “none” was her first pronouncement of the day. – Copyright The Financial Times Limited 2010